In the related art, examples of vibration generators used in devices, such as mobile phones, requiring a vibration mode are a vibration motor in which an eccentric type or eccentric mass type weight is installed in a brush DC motor, a BLOC vibration motor in which an eccentric type weight is installed in a rotor, a coin type vibration motor, a vertical vibration motor using resonance, etc. However, the related art vibration generators are problematic in that they cannot efficiently realize certain requirements, such as long life span, reliability, thinness, and high vibration force that are required by devices such as mobile phones.
For example, the vibration generators using the brush DC motors are problematic in that when a brush passes through a gap between segments of a commutator, the brush induces mechanical friction, electric sparks, and abrasion, thereby producing impurities and reducing the expected life span of the vibration generators.
Further, in an effort to overcome the problems of the vibration generators using the brush DC motors, the vertical vibration motors that move upward and downward using resonance can generate resonance vibration in a moving assembly having both a spring and a weight by causing oscillation in an electromagnetic force due to a mutual interaction between the electromagnetic force and a magnetic field. However, the vertical vibration motors are mechanically problematic in that they have a vertically moving mechanism using an elastic body, and so they inevitably require a mechanical space in which the vibration generators can move upward and downward, and this hinders any efforts to reduce the height of the vibration generator.
Further, in the related art, to install various types of vibration motors in limited spaces of devices such as mobile phones, it is required to form an additional space in the devices for receiving a power supply unit provided in a protruding terminal of the vibration motor. Another problem of the related art vibration motor resides in that it is required to connect a lead wire to an external power supply. Here, to electrically connect the lead wire to the external power supply, soldering is used. However, the connection using soldering is problematic in that it may be poorly soldered, a wire may be broken, or a short may occur. Another problem of the connection using soldering resides in that wiring is difficult to be use because of a limited space.